1. Field of the Invention
The present invention relates generally to accessories for musical instruments, and more particularly to musical instrument tuning devices, and still more particularly to automatic musical instrument tuning devices.
2. Background Discussion
The following patents describing automatic tuning devices use electromechanical devices to change or maintain pitch.
US Patent Application Pub. No. 20080006140, by Adams, discloses an automatic tuning device for a guitar which includes a recording device for recording a tone generated by striking a string and for the output of a digital signal corresponding to the recorded tone, a memory device for storage of given digital signals which correspond to a desired tone, a comparator device for comparison of the digital signal output by the recording device with a digital signal corresponding to the desired tone stored in the memory device, an adjuster device for altering the tension of the strings, at least one actuator, for operating the adjuster device, a controller connected to the comparator device, which controls the at least one actuator using a bus line, by means of a difference determined in the comparator device between the signals representing the generated tone and the desired tone.
US Patent Application Pub. No. 20070240554, by Hany, teaches an attachable string tension control device for adjusting the pitch of each string of a musical instrument. The invention purportedly allows a user to switch instantly between a variety of pre-selected tunings and includes a housing with a plurality of string tension and string height adjustment elements, an attaching system to attach the tuning system to a musical instrument, and a clamping system, and a shaft having a handle for connecting the manual force applied to it to the string tension elements.
US Patent Application Pub. No. 20070214935, by Lyles, teaches a stringed musical instrument tuning device using springs to apply tension to corresponding musical strings. Each spring is chosen and configured to impart a string tension generally matched to the appropriate tension of the string at perfect tune. The spring is selected and arranged so that the tension in the string maintains at or near perfect tune even as the string elongates or contracts over time. In one embodiment, once a string is placed in appropriate tune, a mechanical visual indicator is set. As such, if the string tune changes due to elongation or contraction, the change is reflected by misalignment of the mechanical visual indicator even if the change cannot be aurally detected. Lyles claims to reestablish and maintain perfect tune by realigning the indicator or interposing a force modulating member between a spring and its corresponding musical string such that the tension applied to the string by the spring is not linearly related to the force exerted by the spring as the spring changes in length.
US Patent Application Pub. No. 20060037459, by Skinn, describes an apparatus and a method for self-tuning stringed musical instruments with an accompanying vibrato mechanism. The tuning system includes a detector for detecting a first musical tone produced by a string and for producing a signal value corresponding to that tone; a processor coupled to the detector to compare the signal to a reference frequency value associated with a desired frequency and to produce an electrical control signal, which is a function of the difference between the signal value and the reference frequency value; and a string adjustment assembly coupled to the processor and to the string for adjusting the tension of the string in accordance with the electrical control signal. The string adjustment assembly comprises a motor and gear assembly pivotally attached to a housing.
The above-described systems and devices mentioned all require considerable permanent alterations of the musical instrument in or on which they are installed (viz., guitars). The effect is that the tuning systems cannot be easily moved from one guitar to another, and permanent alterations to the guitar can be expected to adversely affect the sound of the instrument.
U.S. Pat. No. 6,278,047 describes an apparatus for tuning stringed instruments in which each string of the instrument is connected to a corresponding sensor and a tensioning driver. The sensor provides to a microprocessor controller a real time value of the tension in the string. A computer receives the real time tension value from the microprocessor and compares it to a predetermined reference value. Feedback information is provided to the microprocessor, which commands the driver to adjust the string tension accordingly. The tuner does not remain coupled to the instrument. Rather, it is attached, operated, and detached when the tuning operation is completed. This gives it the advantage of being adaptable for use with a number of different kinds of stringed instruments, but it also lacks mobility and ease of use. Every time a user wants to tune an instrument, he or she must unplug everything and connect the instrument to the tension sensing device. After tuning, he or she can then continue using the instrument.
The foregoing patents and patent applications reflect the current state of the art of which the present inventor is aware. Reference to, and discussion of, these patents is intended to aid in discharging Applicant's acknowledged duty of candor in disclosing information that may be relevant to the examination of claims to the present invention. However, it is respectfully submitted that none of the above-indicated patents disclose, teach, suggest, show, or otherwise render obvious, either singly or when considered in combination, the invention described and claimed herein.